Nominations for the Sinn Fein leadership will close at 5pm on Friday with Mary Lou McDonald expected to be named as the only candidate.
Mrs McDonald, the party's current deputy leader, has long been the favourite to succeed outgoing Sinn Fein president Gerry Adams, who has held the position since 1983.
On social media there has been widespread support for the Dublin Central TD to take the position.
In a video posted to Twitter Fiachra McGuinness, son of former deputy first minister Martin McGuinness, offered his support to Mrs McDonald.
"I am proud and honoured to endorse Mary Lou McDonald," he said.
"My father worked closely with Mary Lou for many years in the Sinn Fein leadership, and was a huge admirer of her ideas, dedication, and commitment," he said.
He said Mrs McDonald was the "ideal candidate" to "lead Sinn Fein into the future".
Other high-profile party members who have given their backing to Mrs McDonald are MEP Martina Anderson, Wicklow TD John Brady, and former Westminster candidate John Finucane.
Gerry Adams announced he would be stepping down as the leader of the party in November of last year at the party's Ard Fheis in Dublin, saying it would be his last as leader.
A special Ard Fheis is set to take place on February 10 for the new leader to be confirmed.
The party had said it will hold a series of debates ahead of this to allow candidates to address party members.
After last November's Ard Fheis, Sinn Fein's Stormont leader Michelle O'Neill ruled herself out of the running for the party's leadership as too did Pearse Doherty who was considered a possible contender.
Sinn Fein president Gerry Adams (R) and Northern Sinn Fein leader Michelle O'Neill (L) lay the Irish flag on the coffin of former Northern Ireland Deputy First Minister Martin McGuinness before it is processed through the Bogside neighbourhood of Derry to his family home on March 21, 2017. AFP/Getty Images
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry by Gerry Adams and Michelle O'Neill after he died aged 66. Pic: Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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Sinn Fein President Gerry Adams and Michelle O'Neill, stand over the coffin of former deputy first minister and ex-IRA commander Martin McGuinness as it is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is placed on a stand as it is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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Message placed on the wall of Connolly House, Andersonstown, Belfast, from Gerry Adams after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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The wife of former Northern Ireland Deputy First Minister Martin McGuinness, Bernie (R), helps to carry the coffin of her late husband in procession through the Bogside neighbourhood of Derry to his family home on March 21, 2017. AFP/Getty Images
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Sinn Fein President Gerry Adams (R) and Northern Ire;and Leader, Michelle O'Neill (L) adjusts an Irish flag on the coffin of the late Martin McGuinness watched by his wife Bernadette McGuinness (C) on March 21, 2017 in Derry (Photo by Charles McQuillan/Getty Images)
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Sinn Fein President, Gerry Adams (R) and Sinn Fein Northern Leader, Michelle O'Neill (L) comfort a mourner as they await the coffin of the late Martin McGuinness on March 21, 2017 in Derry (Photo by Charles McQuillan/Getty Images)
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Sinn Fein President Gerry Adams (R) and Sinn Fein Northern Ireland leader, Michelle O'Neill (L) carry the coffin of the late Martin McGuinness past Free Derry corner on March 21, 2017 in Derry, Northern Ireland. (Photo by Charles McQuillan/Getty Images)
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An Irish Flag flys at half mast in the Bogside neighbourhood of Derry on March 21, 2017 as a mark of respect after the death of former Northern Ireland Deputy First Minister Martin McGuinness. AFP/Getty Images
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Bernadette McGuinness (R) carries the coffin of her late husband Martin McGuinness on March 21, 2017 in Derry, Northern Ireland. (Photo by Charles McQuillan/Getty Images)
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Well wishers carry the coffin of the late Martin McGuinness past the murals at Free Derry corner on March 21, 2017 in Derry, Northern Ireland. (Photo by Charles McQuillan/Getty Images)
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Well wishers carry the coffin of the late Martin McGuinness past the murals at Free Derry corner on March 21, 2017 in Derry, Northern Ireland. (Photo by Charles McQuillan/Getty Images)
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Well wishers carry the coffin of the late Martin McGuinness past the murals at Free Derry corner on March 21, 2017 in Derry, Northern Ireland. (Photo by Charles McQuillan/Getty Images)
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The sons of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness , Fiachra (left) and Emmet, carry his coffin to his home in Derry after he died aged 66. Pic: Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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Mourners pictured at the removal of Sinn Fein's Martin McGuinness to his home in the Bog side. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Fein's Martin McGuinness to his home in the Bog side. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Martin's wife Bernie pictured during her husband's removal. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Martin's wife Bernie pictured during her husband's removal. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Martin's wife Bernie pictured during her husband's removal. Photo by Stephen Hamilton / Press Eye.
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Presseye Stephen Hamilton
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Sinn Feins president Gerry Adams Presseye
Mourners pictured at the removal of Sinn Feins Martin McGuinness to his home in the Bog side. Sinn Feins president Gerry Adams
The sons of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness , Fiachra (left) and Emmet, carry his coffin to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry by his wife Bernie McGuinness (front right) after he died aged 66. Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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Sinn Fein President Gerry Adams and Michelle O'Neill, stand over the coffin of former deputy first minister and ex-IRA commander Martin McGuinness as it is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is placed on a stand as it is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
PA
The coffin of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness is carried to his home in Londonderry after he died aged 66. Niall Carson/PA Wire
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A flag flies at half mast in the bogside area of Londonderry after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Pic: Niall Carson/PA Wire
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A flag flies at half mast in the bogside area of Londonderry after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Niall Carson/PA Wire
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A Derry Country GAA flag flies at half mast in the bogside area of Londonderry after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Niall Carson/PA Wire
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A passerby stops at the gates of Connolly House, Andersonstown, Belfast to read a message from Gerry Adams after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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Constituency staff of Belfast West MLA Alex Maskey tie lilies to the gates of Connolly House, Andersonstown, Belfast, after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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Constituency staff of Belfast West MLA Alex Maskey tie lilies to the gates of Connolly House, Andersonstown, Belfast, after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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Constituency staff of Belfast West MLA Alex Maskey placing a message from Gerry Adams to the gates of Connolly House, Andersonstown, Belfast, after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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Constituency staff of Belfast West MLA Alex Maskey tie lilies to the gates of Connolly House, Andersonstown, Belfast, after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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Lilies left in remembrance to Martin McGuinness at the gates of Connolly House, Andersonstown, Belfast, after the death of Northern Ireland's former deputy first minister and ex-IRA commander aged 66. Liam McBurney/PA Wire
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A passer by stops at the gates of Connolly House, Andersonstown, Belfast to read a message from Gerry Adams after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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William Cosgrove signs the book of condolence in remembrance to Martin McGuinness at Connolly House, Andersonstown, Belfast, after the death of Northern Ireland's former deputy first minister and ex-IRA commander aged 66. Liam McBurney/PA Wire
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A floral tribute left at the gates of Connolly House, Andersonstown, Belfast following the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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A woman carries a child past a Republican mural in the Bogside neighbourhood of Derry in Northern Ireland on March 21, 2017 near the home of former deputy first minister Martin McGuinness, whose death was announced this morning.
Martin McGuinness, a one-time Irish Republican Army commander who later helped negotiate an end to the conflict in Northern Ireland, has died aged 66. His Sinn Fein party, which opposes British rule in Northern Ireland and was long considered the political arm of the IRA, announced the death in a statement on March 21, 2017, expressing "deep regret".
/ AFP PHOTO / Paul FAITHPAUL FAITH/AFP/Getty Images
AFP/Getty Images
Murals in the bogside area of Londonderry after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Niall Carson/PA Wire
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A general view of the bogside area of Londonderry after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Niall Carson/PA Wire
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A black flag and the national flag of Ireland referred to as the Irish tricolour, fly at half mast at Connolly House, Andersonstown, Belfast following the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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A black flag and the national flag of Ireland referred to as the Irish tricolour, fly at half mast at Connolly House, Andersonstown, Belfast following the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. PRESS ASSOCIATION Photo. Picture date: Tuesday March 21, 2017. Mr McGuinness stood down in January in protest at the DUP's handling of the 'cash for ash' energy scandal, triggering a snap election. See PA story DEATH McGuinness. Photo credit should read: Liam McBurney/PA Wire
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Floral tributes left at the gates of Connolly House, Andersonstown, Belfast following the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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A woman leaves flowers at the gates of Connolly House, Andersonstown, Belfast after the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
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Sinn Fein for Belfast City Council Emma Groves signs the book of condolence at Connolly House, Andersonstown, Belfast, following the death of Northern Ireland's former deputy first minister and ex-IRA commander Martin McGuinness aged 66. Liam McBurney/PA Wire
Sinn Fein president Gerry Adams (R) and Northern Sinn Fein leader Michelle O'Neill (L) lay the Irish flag on the coffin of former Northern Ireland Deputy First Minister Martin McGuinness before it is processed through the Bogside neighbourhood of Derry to his family home on March 21, 2017. AFP/Getty Images